*5.1.4. Calicivirus induced vesicular disease*

Smith and co-workers [53] reported an Atlantic bottlenose dolphin with vesicular skin disease caused by calicivirus. This disease was apparently transferred to another dolphin, but via a sea lion. The lesions eventually eroded and left shallow ulcers. Interestingly, serological studies on mysticete spp. from the North Pacific, showed the presence of neutralizing bodies to several marine vesiviruses, including calicivirus [54].

Cutaneous Lesions in Cetaceans: An Indicator of Ecosystem Status? 135

cetaceans, including bottlenose dolphins, belugas and pseudorca's.

symptoms, such as granulomas in various organs and lymph nodes,

bacterium cells, and generally occurs in water. These bacteria often colonize wounds, which can lead to septicaemia [14]. *Pseudomonas aeruginosa* had been reported to form large cutaneous ulcers in Atlantic bottlenose dolphins, penetrating deep into the tissue and consequently leading to serious conditions in the affected animals. Septicaemia develops when the bacteria proliferate into the walls of

by Varaldo and co-workers [27]. Moreover, this represented the first report of an association between this genus and cetaceans. *S. delphini*  isolates were obtained from suppurative skin lesions in two captive dolphins which recovered rapidly after antibiotic treatment [27].

residents of cetacean's skin and upper respiratory tract. Cutaneous

opportunistic and associated with animals under stress of some sort [51]. Species from this genus have been isolated from cetaceans with skin lesions [55], septicaemia, metritis and pneumonia. Amazon River dolphins have been reported with a specific dermatological condition, commonly known as 'golf ball disease', caused by *Streptococcus iniae*, and characterized by the presence of slow-

commonly isolated bacteria from stranded cetaceans. The two species specifically associated with skin lesions, were *Vibrio alginolyticus* and *Vibrio parahaemolyticus* originating from Atlantic bottlenose dolphins (*T. truncatus*) from Florida and New Jersy (USA). Dhermain and co-workers [58] also implicated bacteria from

infections caused by these species, are therefore usually

growing, nodular, subcutaneous abscesses [56].

*Vibrio* Buck and co-workers [55] found that *Vibrio* spp. were the most

this genus, in cases of cetacean septicaemias.

**Table 1.** Bacterial species reported to cause skin lesions in cetaceans

In the infected animals, non-healing, chronic cutaneous or subcutaneous lesions were present and associated with other

the blood vessels [56]. A *Pseudomonas* sp. and *Pseudomonas putrefaciens,* had also been isolated from skin lesions in Atlantic

bottlenose dolphins by Buck and co-workers [55].

*Staphylococcus* A new species in this genus, *Staphylococcus delphini,* was described

*Streptococcus Streptococcus* bacteria are Gram positive diplococci and common

**Bacterial genus Bacterial species occurring on cetaceans**

*Mycobacterium* Species of *Mycobacterium* have been associated with infections in

as well as pulmonary infections [56]. *Pseudomonas* This genus is known for Gram negative, motile, slender bacillus
